lwip: add net_lwip_dns_resolve()

Add a helper fonction to convert an IP address (supplied as a text
string) or a host name to an ip_addr_t.

Signed-off-by: Jerome Forissier <[email protected]>

1 files changed, 39 insertions, 0 deletions

diff --git a/net/lwip/net-lwip.c b/net/lwip/net-lwip.c
index 040b51e8852..3918d57d7e5 100644
--- a/net/lwip/net-lwip.c
+++ b/net/lwip/net-lwip.c
@@ -7,6 +7,7 @@
 #include <dm/device.h>
 #include <dm/uclass.h>
 #include <hexdump.h>
+#include <linux/kernel.h>
 #include <lwip/ip4_addr.h>
 #include <lwip/dns.h>
 #include <lwip/err.h>
@@ -358,6 +359,44 @@ int net_lwip_rx(struct udevice *udev, struct netif *netif)
 	return len;
 }
 
+/**
+ * net_lwip_dns_resolve() - find IP address from name or IP
+ *
+ * @name_or_ip: host name or IP address
+ * @ip: output IP address
+ *
+ * Return value: 0 on success, -1 on failure.
+ */
+int net_lwip_dns_resolve(char *name_or_ip, ip_addr_t *ip)
+{
+#if defined(CONFIG_CMD_DNS)
+	char *var = "_dnsres";
+	char *argv[] = { "dns", name_or_ip, var, NULL };
+	int argc = ARRAY_SIZE(argv) - 1;
+#endif
+
+	if (ipaddr_aton(name_or_ip, ip))
+		return 0;
+
+#if defined(CONFIG_CMD_DNS)
+	if (do_dns(NULL, 0, argc, argv) != CMD_RET_SUCCESS)
+		return -1;
+
+	name_or_ip = env_get(var);
+	if (!name_or_ip)
+		return -1;
+
+	if (!ipaddr_aton(name_or_ip, ip))
+		return -1;
+
+	env_set(var, NULL);
+
+	return 0;
+#else
+	return -1;
+#endif
+}
+
 void net_process_received_packet(uchar *in_packet, int len)
 {
 #if defined(CONFIG_API) || defined(CONFIG_EFI_LOADER)